A battery pack consists of one or more secondary (rechargeable) electrochemical cells or batteries, wherein each cell typically includes a positive electrode, a negative electrode, and an electrolyte or other material for facilitating movement of ionic charge carriers between the negative electrode and positive electrode. As the cell is charged, cations migrate from the positive electrode to the electrolyte and, concurrently, from the electrolyte to the negative electrode. During discharge, cations migrate from the negative electrode to the electrolyte and, concurrently, from the electrolyte to the positive electrode.
Compounds of the formula VOXO4 (X=S, P or As) are known to be suitable for use as electrode active materials in lithium anode-based secondary electrochemical cells (Li//VOXO4). However, these materials must be lithiated in order to make these materials useful in a lithium-ion cell (e.g. a cell containing a graphitic negative electrode). Lithiation of these electrode active materials can be accomplished chemically using lithiating agents such as butyl lithium and lithium iodide. However, such chemical lithiation techniques are expensive, slow and produce low yields, therefore making them unsuitable for commercial use.
Accordingly, there is a current need for a method of making compounds of the formula AVOXO4 (A=an alkali metal, and X=S, P or As), which is easier, faster, less expensive and/or produces greater yields, than those methods known in the art.